From 810701d939114a5fcdacc55ec383de112c5e3fa4 Mon Sep 17 00:00:00 2001
From: Eric Wong <e@yhbt.net>
Date: Mon, 17 Jan 2011 03:42:33 +0000
Subject: [PATCH] ev_core: reuse buffer to avoid GC thrashing

Single-threaded concurrency models can reuse a single
buffer to avoid thrashing memory and causing unnecessary
GC activity.
---
 lib/rainbows/coolio/client.rb                     | 2 +-
 lib/rainbows/ev_core.rb                           | 1 +
 lib/rainbows/event_machine/response_chunk_pipe.rb | 2 +-
 lib/rainbows/event_machine/response_pipe.rb       | 4 ++--
 4 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/lib/rainbows/coolio/client.rb b/lib/rainbows/coolio/client.rb
index f44d2aa..2947462 100644
--- a/lib/rainbows/coolio/client.rb
+++ b/lib/rainbows/coolio/client.rb
@@ -44,7 +44,7 @@ class Rainbows::Coolio::Client < Coolio::IO
   end
 
   def on_readable
-    buf = @_io.kgio_tryread(16384)
+    buf = @_io.kgio_tryread(16384, RBUF)
     case buf
     when :wait_readable
     when nil # eof
diff --git a/lib/rainbows/ev_core.rb b/lib/rainbows/ev_core.rb
index a3bf50f..b9b3381 100644
--- a/lib/rainbows/ev_core.rb
+++ b/lib/rainbows/ev_core.rb
@@ -7,6 +7,7 @@ module Rainbows::EvCore
   NULL_IO = Unicorn::HttpRequest::NULL_IO
   HttpParser = Rainbows::HttpParser
   autoload :CapInput, 'rainbows/ev_core/cap_input'
+  RBUF = ""
 
   # Apps may return this Rack response: AsyncResponse = [ -1, {}, [] ]
   ASYNC_CALLBACK = "async.callback".freeze
diff --git a/lib/rainbows/event_machine/response_chunk_pipe.rb b/lib/rainbows/event_machine/response_chunk_pipe.rb
index 5caf250..af9393a 100644
--- a/lib/rainbows/event_machine/response_chunk_pipe.rb
+++ b/lib/rainbows/event_machine/response_chunk_pipe.rb
@@ -10,7 +10,7 @@ module Rainbows::EventMachine::ResponseChunkPipe
 
   def notify_readable
     begin
-      data = @io.read_nonblock(16384, BUF)
+      data = @io.read_nonblock(16384, RBUF)
       @client.write("#{data.size.to_s(16)}\r\n")
       @client.write(data)
       @client.write("\r\n")
diff --git a/lib/rainbows/event_machine/response_pipe.rb b/lib/rainbows/event_machine/response_pipe.rb
index 3b584c7..0ea1eae 100644
--- a/lib/rainbows/event_machine/response_pipe.rb
+++ b/lib/rainbows/event_machine/response_pipe.rb
@@ -3,7 +3,7 @@
 module Rainbows::EventMachine::ResponsePipe
   # garbage avoidance, EM always uses this in a single thread,
   # so a single buffer for all clients will work safely
-  BUF = ''
+  RBUF = Rainbows::EvCore::RBUF
 
   def initialize(client)
     @client = client
@@ -11,7 +11,7 @@ module Rainbows::EventMachine::ResponsePipe
 
   def notify_readable
     begin
-      @client.write(@io.read_nonblock(16384, BUF))
+      @client.write(@io.read_nonblock(16384, RBUF))
     rescue Errno::EINTR
     rescue Errno::EAGAIN
       return
-- 
2.11.4.GIT